A tissue engineering has recently attracted an attention as a convergence technology which is intended to be used for clinical treatment by maintaining, enhancing, restoring or replacing vital functions through a combinatory use of cells, engineering materials and appropriate physiological/biochemical factors etc.
The most fundamental technique of this tissue engineering is to attach cells separated from a biological tissue to porous scaffolds made of a biodegradable polymer and to transplant them in vivo or to culture them for a certain period of time in vitro to produce new biological tissues. As it is used in various fields such as restoring or replacing a part or whole of tissues such as bones, cartilage, blood vessels, bladder, skin or muscles, etc., advancement of bio-environmental simulation technology as well as biomaterials, cells, and biologically active factors is essential to develop artificial tissues/organs for the advance of tissue engineering,
So far, cell culture methods have been based on culturing cells on a two-dimensional (2D) surface of substrates composed of polystyrene or glass so as to support the growth of adherent cells. However, since a monolayer cell culture method of culturing on the 2D surface cannot accurately reflect the biotissue environment of the three-dimensionally grown cells attached to the extracellular matrix, there are many differences between two-dimensional and the body tissue environment of the cell. As a result, 2D cell culture and three-dimensional (3D) cell culture show overall morphological differences, and phenomena occurring in the actual tissue environment such as expression of receptor, gene transcription regulation, cell migration and apoptosis, are different from those which occur through conventional 2D cell culture.
In addition, because the same cell type is generally cultured in the conventional 2D cell culture, it is difficult to observe interactions between different cell types. Although some attempts have been made to solve these problems partially through 2D co-culture, this 2D co-culture cannot fully mirror the cellular environment in living tissues.
In order to solve the problems of the 2D cell culture, there is a need for research and development of a 3D cell culture method taking account of the spatial organization of the cells. As a method of constructing a simulated cell culture environment for a living cell to solve the problem, research and development have been carried out in order to build a 3D cell culture environment by culturing cells in a porous biocompatible scaffold. As a results, studies on how to manufacture scaffolds using synthetic polymers and natural polymers and on precise cell culture methods specific to the tissues to be studied have been progressed.
However, to date, methods for the production of scaffolds most suitable for regenerating living tissues are not yet known.